.single {
    width: 40px;
    height: 40px;
}

.single em {
    margin: 0 auto;
    cursor: pointer;
    display: block;
    font-size: 20px;
    text-align: center;
    line-height: 40px;
}

.single em:after {
    content: '';
    position: absolute;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    margin-top: -40px;
    margin-left: -40px;
    z-index: 3;
    opacity: 0;
    -webkit-animation: halo 2s 0s infinite ease-out;
    -moz-animation: halo 2s 0s infinite ease-out;
    animation: halo 2s 0s infinite ease-out;
    background-color: rgba(51, 202, 198, 0.5);
}

.single em:before {
    content: '';
    position: absolute;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    margin-top: -25px;
    margin-left: -25px;
    z-index: 4;
    opacity: 0;
    -webkit-animation: halo 1s 1s infinite ease-out;
    -moz-animation: halo 1s 1s infinite ease-out;
    animation: halo 1s 1s infinite ease-out;
    background-color: rgba(51, 202, 198, 0.5);

}

.single_red {
    width: 40px;
    height: 40px;
}

.single_red em {
    margin: 0 auto;
    cursor: pointer;
    display: block;
    font-size: 20px;
    text-align: center;
    line-height: 40px;
}

.single_red em:after {
    content: '';
    position: absolute;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    margin-top: -40px;
    margin-left: -40px;
    z-index: 3;
    opacity: 0;
    -webkit-animation: halo 2s 0s infinite ease-out;
    -moz-animation: halo 2s 0s infinite ease-out;
    animation: halo 2s 0s infinite ease-out;
    background-color: rgba(255, 0, 0, 0.5);
}

.single_red em:before {
    content: '';
    position: absolute;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    margin-top: -25px;
    margin-left: -25px;
    z-index: 4;
    opacity: 0;
    -webkit-animation: halo 1s 1s infinite ease-out;
    -moz-animation: halo 1s 1s infinite ease-out;
    animation: halo 1s 1s infinite ease-out;
    background-color: rgba(255, 0, 0, 0.5);
}

@-webkit-keyframes halo {
    0% {
        opacity: 0;
        -webkit-transform: scale(0.1);
    }
    50% {
        opacity: 1;
    }
    100% {
        opacity: 0;
        -webkit-transform: scale(1.2);
    }
}

@-moz-keyframes halo {
    0% {
        opacity: 0;
        -moz-transform: scale(0.1);
    }
    50% {
        opacity: 1;
    }
    100% {
        opacity: 0;
        -moz-transform: scale(1.2);
    }
}

@-ms-keyframes halo {
    0% {
        opacity: 0;
    }
    50% {
        opacity: 1;
    }
    100% {
        opacity: 0;
    }
}

@-o-keyframes halo {
    0% {
        opacity: 0;
        -o-transform: scale(0.1);
    }
    50% {
        opacity: 1;
    }
    100% {
        opacity: 0;
        -o-transform: scale(1.2);
    }
}

@keyframes halo {
    0% {
        opacity: 0;
        transform: scale(0.1);
    }
    50% {
        opacity: 1;
    }
    100% {
        opacity: 0;
        transform: scale(1.2);
    }
}